copy raid array

I have a RAID 5 array consisting of three 9Gb SCSI hard drives in my NT4
server. The array is partitioned into c and d drives. I want to install
one large SCSI drive and copy the entire contents of the old array to
the new single hard drive. I need to clone the C drive especially
because there is software that was installed by our parent company in
the US. My research so far tells me that if I break the array (to add a
drive to it, for example), I will lose everything that is currently on
it (like a drive format). Does anyone know how I can do this. Thanks
in advance for any help.
Doug

If my memory serves me ( some times it simply escapes) I once tried to
copy only the C drive in a raid, and lost the entire setup. ( being the
idea of the raid is to share all information ( redundantly) across all
the drives .
I would suggest a back up first then add the drive and re set the raid
to the new configuration. then try cloning the backup onto the new
raid.... or
the following is in unix, however the info should apply to Raid 5.

* *RAID-5*
o This is perhaps the most useful RAID mode when one wishes to
combine a larger number of physical disks, and still
maintain some redundancy. RAID-5 can be used on *three *or
more disks, with zero or more spare-disks. The resulting
RAID-5 device size will be (N-1)*S, just like RAID-4. The
big difference between RAID-5 and -4 is, that the parity
information is distributed evenly among the participating
drives, avoiding the bottleneck problem in RAID-4.
o *If one of the disks fail, all data are still intact*,
thanks to the parity information. /If spare disks are
available, reconstruction will begin immediately after the
device failure./ *If two disks fail simultaneously, all data
are lost*. RAID-5 can survive one disk failure, but not two
or more.
o Both read and write performance usually increase, but can be
hard to predict how much. Reads are similar to RAID-0 reads,
writes can be either rather expensive (requiring read-in
prior to write, in order to be able to calculate the correct
parity information), or similar to RAID-1 writes. The write
efficiency depends heavily on the amount of memory in the
machine, and the usage pattern of the array. Heavily
scattered writes are bound to be more expensive.

Spare disks

Spare disks are disks that *do not take part in the RAID* set until one
of the active disks fail. When a device failure is detected, that device
is marked as ``bad'' and /reconstruction is immediately started on the
first spare-disk available./

Thus, spare disks add a nice extra safety to especially RAID-5 systems
that perhaps are hard to get to (physically). One can allow the system
to run for some time, with a faulty device, since all redundancy is
preserved by means of the spare disk.

You cannot be sure that your system will keep running after a disk crash
though. The RAID layer should handle device failures just fine, but SCSI
drivers could be broken on error handling, or the IDE chipset could lock
up, or a lot of other things could happen.

Also, once reconstruction to a hot-spare begins, the RAID layer will
start reading from all the other disks to re-create the redundant
information. If multiple disks have built up bad blocks over time, the
reconstruction itself can actually trigger a failure on one of the
"good" disks. This will lead to a complete RAID failure. If you *do
frequent backups of the entire filesystem on the RAID array*, then it is
highly unlikely that you would ever get in this situation - this is
another very good reason for taking frequent backups. Remember, RAID is
not a substitute for backups.

SO
I would first add the new drive as a HOT active spare... this is where
My knowledge will need some help. perhaps some one else in the group
will know how to ( Create) a drive fail situation that will trigger the
hot spare.
the above is only some thinking out loud on my part, I have not used
any raid systems lately, with the event of huge IDE drives which are now
faster and more dependable, I can afford to simply make a redundant
system using a spare (IDE) and if the system fails, swap out the bad
drive for the newer one.

In any case do a system backup before you do anything else.

Note: The above information is given with out charge in an effort to
help with the situation. I may be contacted if there are any
questions that could further help.
remember there is no substitute for BACKUP. good luck.
Pat S.
Saint Croix F/x
www.saintcroixfx.com

thanks for the suggestions. Remember the array is actually three 9 gb
drives, giving me 18 Gb striped and that is partitioned into a 2 Gb
c-drive and the a 16 Gb d-drive. The purpose of doing this is to get
more space on the c-drive. Are you sure that Norton Ghost will do
this? Thanks.
Doug

Caution. Recently I created exactly what you are talking about. The one of
the physical drives in the strip set failed. This took out my OS and
everything. Had to rebuild everything. Fortunatlly this was not in
production.

It was suggested to me to have the os on a separated logical raid the all of
the data on a second logical raid. If a physical failed on the data drive,
it did not effect the OS drive.

Remember one problem with Ghost is licensing, if you can do th imaging via
a bios duplicator, this will not only save you time, but money..